My native social media is tumblr, that fact obviously has a strong affect on my perception of internet discourse, but I'd like to give my personal thought on this particular topic, that is, internet privacy.
To begin, I think that phrase is basically an oxymoron. Growing up we were taught to never give out personal information on the internet, because you never know for sure who is on the other side of the screen. In my younger days I definitely didn't always follow this advice, and I got lucky that it never came back to bite me. I made a lot of friends on the internet, I've even met some in person, and theres one friend I met when I was 15 that I still talk to to this day. I absolutely think one can form meaningful relationships on the internet, one couple that I introduced to each other on the internet got married a couple years ago. But one thing we always knew, once something is on the internet, it's there forever. We were careful, most of the time, but we were also dumb kids.
Today's generation is growing up with constant internet access, and they're smart, they understand how powerful the internet it, and how to use it to their benefit, but, just like we all once were, they're still dumb kids.
My generation, and people older than me, grew up in a different time, most, if not all, the contact we had with people growing up was in person instead of digital, and when you meet someone in person you are able to observe things about a person, their approximate age, your perception of their gender, their skin color, and you make decisions about how to interact with people based on these factors. Most of us grew up having this context when interacting with someone, we think these things are important to know, because it tells us if we should treat the other person with respect or dignity. We all have biases, and in an interaction with someone you don't know anything about, you only have two options, the two categories you group everyone into subconsciously, or consciously, "human" and "not human", "deserving of respect" and "not deserving of respect." and a lot of us, when we have the anonymity that the internet provides, feel more comfortable putting other in the "not like me" category, and treating people as less than human. This includes feeling entitled to information from other people.
We can feel entitled to know the things we could perceive by seeing someone in person. Their age, skin color, height, weight, disability status, and often times even more personal information than that. And thats just everyday people like you and me, don't get me started on the information we feel entitled to from celebrities.
I have seen people say they need to know if someone that interacts with their post is a minor or an adult, they felt entitled to that information. Can we all see how fucking ridiculous that is? And how unsafe it can be for a minor to reveal that information publicly on the internet? Attempting to create a norm of sharing personal information online, and pressuring children into revealing private data about themselves is an incredibly dangerous expectation to set. You are not entitled to anyone's personal information.
"Hey guys! My brain is still not fully developed, and I'm very susceptible to manipulation and abuse because I'm a child, and I'm still learning how the world works! Who wants to warp my perception of what is normal human interaction?!"
And lets not forget the other factors at play. People can lie, children can lie and say they're adults, adults can lie and say they're children, you have no way of verifying anything anyone tells you about themselves. When I was a teenager going through puberty, no DNI or "I'm over 18" button was going to stop me from looking up porn, I could just lie. If you're worried about minors interacting with or seeing your content, then post it somewhere that isn't a public social media platform. Thats like putting up a poster on a telephone poll and getting mad if a kid walks by and looks at it, or publishing your diary, but condemning anyone who buys/reads it, you put it in a public place, if you don't want it to be seen publicly, then go somewhere else or change your privacy settings. You are not entitled to other people's information just because they liked your post, if you genuinely don't want them interacting with you for whatever reason, you can block them, that is your right. And if you think that someone not giving out personal information is good justification for blocking someone, who am I to stop you. But if you go around saying that people have to put their age, or race, or religion, or whatever other information that you feel entitled to, in a public place, that is where it becomes an issue. Especially if your reasoning for 'needing' this information is to know what kind of bigoted remark is most going to be the most offensive, maybe you should talk to a professional. Maybe instead of spreading bigotry and hate you could try pretending the stranger on the other side of the screen is someone you know, or love, or care about, maybe you can try treating other people with decency and respect. I promise the world is a lot less scary when you do.
Why DNIs don't work
They don't work because the people who are going to target you for your beliefs aren't going to care if you ask them super niceys not to. And the people who will respect them probably didn't want to interact with you in the first place, and if they did, guess what, you can block them, or they can block you. DNIs aren't going to keep children from viewing porn if thats what they want to do, they'll either lie, or look at it anyway and just not 'like, comment, or subscribe.' The only way to make for absolute certain that the people you don't want interacting with your posts don't interact with your posts is to not post them. Once something is on the internet its there forever, even if you block someone, there are ways around that if they're that dedicated. There is no way to curate your online experience that much, and if it distresses you that much to not be in control of everyone else all the time, then I got bad news for you buddy.
If you're not comfortable with certain people seeing your bare naked ass, then maybe don't post pictures of it publicly. Once you've posted something publicly, it is, surprisingly, no longer private. It is your responsibility to enforce your boundaries, it is not stranger's responsibility to make you comfortable, if it bothers you that much, theres a block button.